1. Field of the Invention
The present invention relates to a combined connector in which a plurality of connector housings each including a plurality of terminal storage chambers can be simply connected together in a multiple-stage manner.
2. Description of the Related Art
As a combined connector of this type, there is known a combined connector which is disclosed in Japanese Patent Unexamined Publication No. Hei. 2-223171 and shown in FIGS. 4(a) to 4(c). This conventional combined connector 1, as shown in FIGS. 4(a) and 4(c), is composed of a connector housing 2 arranged on the lower-most stage side, connector housings 2xe2x80x2 and 2xe2x80x2 respectively arranged on the middle stage side and the upper-most stage side, and a cover 8 for covering an opening 3a formed in the connector housing 2xe2x80x2 arranged on the upper-most stage side. In the respective connector housings 2, 2xe2x80x2 and 2xe2x80x2, there are formed a plurality of terminal storage chambers 3b for storing therein terminals (not shown). Also, in the front and rear portions of the two side walls 3 and 3 of each of the connector housings 2, 2xe2x80x2 and 2xe2x80x2, there are provided a pair of triangular-prism-shaped, upwardly located, provisionally securing projection 4 and, downwardly located, finally securing projection 5 in such a manner that they are respectively formed integrally with the side walls 3 and projected therefrom; and, on the opening 3a sides of the two side walls 3, 3, there are provided a pair of triangular-prism-shaped, right and left cover securing projections 6 and 6 formed integrally with and projectingly from the side walls 3, with the provisionally and finally securing projections 4 and 5 located between them.
As shown in FIGS. 4(a), 4(b) and 4(c), at the positions of the two side walls 3 and 3 of the connector housings 2xe2x80x2 and 2xe2x80x2 respectively arranged on the middle and upper-most stage sides, in particular that are respectively opposed to the above-mentioned respective securing projections 4 and 5, there are provided frame-shaped engaging pieces 7 and 7 in such a manner that they are formed integrally with their respective side walls 3 and are projected therefrom. Also, at the positions of the two side portions of the cover 8 that are respectively opposed to the above-mentioned respective securing projections 6, there are provided frame-shaped engaging pieces 9 in such a manner that they are formed integrally with their respective side portions and are projected therefrom. By pressing down the connector housing 2xe2x80x2 on the upper-most stage side, as shown in FIG. 4(c), the combined connector 1 can be assembled. That is, as shown by two-dot chained lines in FIG. 4(b), the engaging pieces 7 are respectively fitted with the finally securing projections 5, and the engaging pieces 9 of the cover 8 are slidingly fitted with the cover securing projections 6, respectively. This completes such assembly of the combined connector 1 as shown in FIG. 4(c). By the way, a similar technology relating to the combined connector 1 is disclosed in FIG. 2 in Japanese Patent Unexamined Publication No. Hei. 4-39822.
However, in the above-mentioned conventional combined connector 1, when the respective connector housings 2, 2xe2x80x2 and 2xe2x80x2 are connected together (combined together), it is difficult to position them (that is, to match the centers thereof with each other): that is, as shown in FIG. 5, when the positions of the engaging pieces 7 are shifted in the right and left directions and, as shown in FIG. 6, when the positions of the engaging pieces 7 are shifted in the back and forth directions, it is difficult to pile up the respective connector housings 2, 2xe2x80x2 and 2xe2x80x2 on top of another and secure them to one another. Also, the piling-up and engaging forces of the respective connector housings 2, 2xe2x80x2 and 2xe2x80x2 are easy to vary and, even after they are combined together, there is a fear that there can be produced a clearance between the respective connector housings 2, 2xe2x80x2 and 2xe2x80x2 due to the insufficient piling-up and engaging forces.
In view of the above-mentioned circumstances, the present invention aims at eliminating the above-mentioned drawbacks found in the conventional combined connectors. Accordingly, it is an object of the invention to provide a combined connector which can prevent the respective connector housings from shifting in position in the back and forth directions and in the right and left directions when they are combined together, can reduce the variations in the engaging forces necessary for fitting engagement between the respective securing projections and engaging recessed portions, and can prevent production of a clearance between the respective connector housings after they are combined together.
In attaining the above object, according to the invention, there is provided a combined connector comprising: a plurality of connector housings each including a plurality of terminal storage chambers therein, the connector housings being piled up on top of another and secured to one another in multiple stages in their connecting direction; a first securing projecting portion which is provided in one of mutually opposing connector housings arranged in the connecting direction; a first securing recessed portion which is provided in the other of the mutually opposing connector housings and into which the first securing projecting portion is fitted; a second securing projecting portion which is provided in the one connector housing in a direction crossing at right angles to the first securing projecting and recessed portions; a second securing recessed portion which is provided in the other connector housing and into which the second securing projecting portion is fitted; and an introducing portion which is provided in at least one of the first and second securing projecting portions.